The invention is directed to a vibration pickup or vibration transducer with a pressure sleeve.
A vibration transducer with a pressure sleeve used as a knock sensor for monitoring the operation of an internal combustion engine in a motor vehicle has already been described in DE-OS 44 03 660. This pressure sleeve is fixedly joined to the structural component part causing the vibrations, in this case, the engine block, via a support area. The vibrations to be detected are knocking noises of the operating internal combustion engine which are conducted via the pressure sleeve to a piezoceramic disk serving as the actual sensor element and accordingly converted into an electric output signal capable of evaluation.
The manner in which this sensor element is arranged on and clamped to the pressure sleeve and the fastening of the pressure sleeve to the vibrating structural component part have a great influence on the method of manufacture. The clamping of the sensor element, including a plurality of individual parts, e.g., a spring and a seismic mass, is carried out in this known vibration transducer by relatively elaborate production steps.
In accordance with the present invention, in a vibration transducer with a pressure sleeve, a seismic mass is provided with an internal thread and is screwable directly to the pressure sleeve for clamping a sensor element of the transducer.